Microchannel-based size detector for airborne particles

Real-time monitoring of airborne particles, or aerosols, is important for protecting human health and conserving earth's environment. To this end, we present a size-selective aerosol sensor, including a centrifugal force based microfluidics device for real-time aerosol size separation. We have achieved separation of bidisperse mixtures of airborne polystyrene latex particles in the range of 0.75 μm to 2.88 μm. This is the first time microchannels have been used to separate aerosols by size using mechanical principles. Our detection system responds to the test particles at concentrations well above and below the regulatory limits. The separation and detection systems together will form a portable sensor suitable for continuous monitoring of aerosols.